File storing method, and storage medium, computer system usable for the file storing method

Abstract

Provided is a storage media, including a nonvolatile semiconductor storage device, from which data is erasable with certainty on a file-by-file basis so that files leaks are prevented to a maximum possible degree. In a file storing method for storing a file in the storage media including a nonvolatile semiconductor storage device having a plurality of erase blocks each including a plurality of memory cells from which data is erasable as a whole, (a) one file is stored to one erase block, or (b) an overwrite operation of writing prescribed data or random data to a bit of a memory cell, at which a file to be erased is stored, is performed.

What is claimed is: 
     
         1 . A file storing method comprising storing a file in a nonvolatile semiconductor storage device including a plurality of erase blocks each including a plurality of memory cells from which data is erasable as a whole, wherein only one file is stored to one erase block. 
     
     
         2 . A file storing method according to  claim 1 , wherein only one file is stored to one erase block or only one file is stored to a plurality of erase blocks in accordance with an instruction from a host-side element. 
     
     
         3 . A file storing method comprising storing a file in a nonvolatile semiconductor storage device, including a plurality of erase blocks each having a plurality of memory cells from which data is erasable as a whole, wherein an overwrite operation of writing prescribed data or random data to a bit of a memory cell, at which a file to be erased is stored, is performed. 
     
     
         4 . A storage medium, comprising a control unit for performing a file storing method according to  claim 1 . 
     
     
         5 . A storage medium, comprising a control unit for performing a file storing method according to  claim 2 . 
     
     
         6 . A storage medium, comprising a control unit for performing a file storing method according to  claim 3 . 
     
     
         7 . A computer system for supplying a control signal for performing a file storing method according to  claim 1  to the storage medium. 
     
     
         8 . A computer system for supplying a control signal for performing a file storing method according to  claim 2  to the storage medium. 
     
     
         9 . A computer system for supplying a control signal for performing a file storing method according to  claim 3  to the storage medium. 
     
     
         10 . Driver software for generating the control signal in  claim 5 .